A high-speed network environment typically includes network devices such as routers and bridges used for facilitating delivery of information packets and/or data traffic from source devices to destination devices. Information pertaining to the transfer of packet(s) through the network is usually embedded within the packet itself. Each packet traveling through one or more communications networks such as Internet and/or Ethernet can typically be handled independently from other packets in a packet stream or traffic. For example, each router which may include routing and bridging engines processes incoming packets and determines where the packet(s) should be forwarded. In a high-speed computing network environment, the speed of packet processing, which includes routing, bridging, and/or both, can be critical in determining the overall performance of a network system.
To route a packet or data stream between Local Area Network (“LAN”) and Wide Area Network (“WAN”), a router typically includes a routing engine and a bridging engine. While the routing engine may be used to handle the routing activities between WAN and the router, the bridging engine is used to forward data packets between LAN and the router. Note that bridging and routing engines are both transporting and controlling data packets, but they work through different methods. Bridging takes place at layer 2 or data link layer while routing takes place at layer 3 or Network Layer. It should be noted that a bridging engine directs frames according to hardware assigned MAC (Media Access Control) addresses while a routing engine makes its decisions according to arbitrarily assigned IP Addresses. Since a bridging engine typically uses a data link layer or layer 2 switch for data forwarding while a routing engine employs a layer 3 switch for passing data packets, transporting a packet from a source via a WAN to a host over a LAN typically requires the packet to travel through both the routing engine and the bridging engine in order to reach its destination.
To forward IP traffic from a routed interface of a routing engine to a bridge-group of a bridging engine, a conventional network device is required to first route the packets, and subsequently bridge each packet to one or more destinations. A problem associated with bridging interface and routing interface is that although a network device may have the capability to route and bridge separate traffic streams at the same time, it is typically unable to run both routing and bridging on the same packet at the same time. Having each packet traveling through both routing and bridging engines while being forwarded from a routed network to a bridged network increases packet latency, which negatively affects the overall network performance.